Constraint Preserving XML Updating

With the rapid development of Internet, XML becomes the standard for data representation, integration and exchange on the web. In order to fully evolve XML into a universal data representation and sharing format, it is necessary to update XML documents efficiently while preserving constraints. We consider an important class of constraints, XML keys. In this paper, based on XML keys and the constraint-preserving normalized storage of XML over relational databases, we present a novel method for updating XML data. Our method first propagates the update on XML into the relational database. Then taking the updated relational data and the original document as input, the resulting XML document updated can be produced through locating the positions of updates in the original one by annotation technology. Preliminary performance studies have shown that our method is very effective and efficient.